/Engine/Source/Runtime/RHI/Public/GPUDefragAllocator.h
Immediately shrinks a memory chunk by moving the base address, without relocating any memory. Always succeeds.
The new shrunken chunk
[FMemoryChunk](API\Runtime\RHI\FGPUDefragAllocator\FMemoryChunk) * Shrink ( [FMemoryChunk](API\Runtime\RHI\FGPUDefragAllocator\FMemoryChunk) * Chunk, int64 ShrinkAmount )